TECHNICAL FIELD
The invention relates generally to devices that provide moveable work platforms underneath a bridge and, more particularly, to devices that permit work platforms to be moveably suspended from the underside of a bridge. Specifically, the invention relates to a suspension device that provides a pair of rails clamped to the lower webs of parallel bridge girders, with a scaffold member being rollably mounted on each rail, and with the work platform being built upon and extending between the two scaffold members.